requirements: update for Python 3 compatibility

Signed-off-by: Gerard Marull-Paretas <gerard@teslabs.com>

requirements-linux.txt

@@ -1,18 +1,18 @@
 #--extra-index-url https://pebble:W9Ngyc3ohHFvLKfUUxmVruCmBaHQxNBCpfDCXyoAwLJgncZmAw@pypi.pbl.io/
-Pillow==2.0.0
-freetype-py==1.0
+Pillow
+freetype-py
 ply==3.4
 pyusb==1.0.0b2
-pyserial==2.7
+pyserial
 sh==1.04
-pypng==0.0.16
+pypng
 pexpect
 cobs==1.0.0
-svg.path==3.0
+svg.path
 requests
 GitPython==1.0.1
-pyelftools==0.23
-pycrypto==2.6.1
+pyelftools
+pycryptodome
 mock
 nose
 boto
@@ -24,11 +24,12 @@ polib
 intelhex>=2.1,<3
 protobuf==3.6
 certifi
+libclang
 
 # pypi.getpebble.com provided modules
 #pebble.loghash>=2.6
 #pebble.programmer>=0.0.4
 #pebble.commander==0.0.11
 libpebble2>=0.0.16
-pyftdi==0.13.2
-pathlib
+pyftdi==0.13.4
+pathlib