ti gel- and cmd-files; add aem4 lib in ccs

Wiki, pdf (gel-file):
1) Creating Device Initialization GEL Files https://www.ti.com/lit/an/spraa74a/spraa74a.pdf

Funcs:
1) https://software-dl.ti.com/ccs/esd/documents/users_guide/gel/GEL_MapOff.html
2) https://software-dl.ti.com/ccs/esd/documents/users_guide/gel/GEL_MapReset.html
3) https://software-dl.ti.com/ccs/esd/documents/users_guide/gel/GEL_MapAddStr.html
4) https://software-dl.ti.com/ccs/esd/documents/users_guide/gel/GEL_LoadGel.html
5) http://software-dl.ti.com/ccs/esd/documents/users_guide_9.3.0/gel/OnTargetConnect.html

cmd-file:
1) https://software-dl.ti.com/ccs/esd/documents/sdto_cgt_Linker-Command-File-Primer.html
2) https://processors.wiki.ti.com/index.php/Linker_CMD_Files_for_CCS
3) Advanced Linker Techniques for Convenient and Efficient Memory Usage 

https://www.ti.com/lit/an/spraa46a/spraa46a.pdf
4) https://processors.wiki.ti.com/index.php/Linker_CMD_Files_for_CCS
5) https://processors.wiki.ti.com/index.php/C28x_Compiler_-_Understanding_Linking
6) http://software-dl.ti.com/ccs/esd/documents/ccs_files_in_projects.html

pragma DATA_SECTION(), CODE_SECTION():
1) Using DATA_SECTION PRAGMA With Defined Memory Section in Linker Command File
https://processors.wiki.ti.com/index.php/Placing_Variables_in_Specific_Memory_Location_-_MSP430#Using_DATA_SECTION_PRAGMA_With_Defined_Memory_Section_in_Linker_Command_File
2) ti c/c++ and assembly language compilers user guides https://www.ti.com/tool/TI-CGT#technicaldocuments
3) #pragma DATA_SECTION() expansion https://e2e.ti.com/support/tools/ccs/f/81/t/277661
4) https://stackoverflow.com/questions/1675351/typedef-struct-vs-struct-definitions
5) #pragma CODE_SECTION('.startup_code') https://e2e.ti.com/support/tools/ccs/f/81/t/41618?-pragma-CODE-SECTION-applying-to-files-groups-of-functions-

.bss:
1) https://en.wikipedia.org/wiki/.bss

add aem4 lib in ccs:
1) https://e2e.ti.com/support/processors/f/791/t/564044?CCS-Undefined-symbol-in-build-for-AM571x-M4

Error connecting to the target: (Error -1170 @ 0x0) Unable to access the DAP:

1) https://e2e.ti.com/support/tools/code-composer-studio-group/ccs/f/code-composer-studio-forum/567337/ccs-tms570ls3137-error-connecting-to-the-target-error--1170-0x0-unable-to-access-the-dap