Update Readme: issue solving

[inxomnyaa]

Stumbeled about plenty issues while compiling, here are fixes:

• Error:

  Could NOT find CURL (missing: CURL_LIBRARY CURL_INCLUDE_DIR)

• Fix:
  apt-get install curl libcurl4-openssl-dev

---

• Error:

CMake Warning at /usr/local/share/cmake-3.8/Modules/FindProtobuf.cmake:387 (message):
  Protobuf compiler version doesn't match library version 2.6.1
Call Stack (most recent call first):
  CMakeLists.txt:8 (find_package)

or

• Error:
  Protobuf_PROTOC_EXECUTABLE-NOTFOUND

• Fix:
  apt-get install libprotobuf-dev protobuf-compiler

---

Have fun everyone!

[MCMrARM]

The install instructions are on the Wiki. I think adding a mention to go to wiki on Readme isn't a bad idea though so I'll leave this open because of this reason for a while.