PCB layout rework and minor update to schematics

See merge request !2

BOM optimization, minor fixes, added 2x thermometer for AD9516 chips.

See merge request !1

[Cleaner PLL] C39, C43, C132: CC0402_1NF_50V_10%_X7R ==> CC0603_1NF_50V_5%_NP0
[Delay] R6: R0603_10R_1%_0.1W_200PPM replaced with 2x parallel R0402_20R_1%_0.0625W_100PPM
[Phase detector] R18, R53: R0603_500R_1%_0.1W_100PPM ==> R0603_499R_0.1%_0.063W_10PPM
[ADC Filter] C15, C22, C25: CC0603_100NF_50V_10%_X7R ==> CC0402_100NF_16V_10%_X7R
[Delay] C50, C82, C84, C105, C116: CC0603_100NF_50V_10%_X7R ==> CC0402_100NF_16V_10%_X7R
[DAC] Added C154 100 nF to DVDD3.3 of IC13
[Cleaner PLL] R78: not mounted ==> 100 Ohm (R0402_100R_1%_0.0625W_100PPM)
[Cleaner PLL] Added B7 and B8 at LD and REFMON outputs of IC26
[ADC Filter] IC19 VIO power port connected to P2V5 via L17
[Delay] Changed note text "MC100LVEL input current is about 100..300uA" ==> "MC100EP29 input current is about 100..300uA"
[Delay] Added note on FF_VBB net
[FMC] Added 2x MCP8901 to be placed under AD9516

Added History/** to .gitignore
Some cosmetic changes to notes.

Addressed review-dec-2018 actions: A2, A9, A15, A16 and A17.
A4 is to be confirmed.

- removed RF divider
- added clock buffer at the DAC output
- replaced vcxo oscillator with 100ppm pull ability

added RF divider, programamble delay

added PDF version for sch and pcb